Dodge Ram Truck 1500-2500-3500. Manual — part 1782

7. Install spring retainer (3) on top of piston springs (9).

8. Compress spring retainer and piston springs with Tool C-3863-A.

9. Install spring retainer snap-ring (8) and remove compressor tool.

10. Install clutch plates and discs (4, 7). Five clutch discs, five steel plates and one reaction plate are required.

11. Install reaction plate (6) followed by waved snap-ring (5).

48RE Front Clutch Components

1 - INNER PISTON SEAL

7 - CLUTCH DISCS

2 - CLUTCH PISTON

8 - RETAINER SNAP-RING

3 - CLUTCH PISTON SPRING RETAINER

9 - CLUTCH PISTON SPRINGS

4 - CLUTCH PLATES

10 - OUTER PISTON SEAL

5 - CLUTCH PACK SNAP-RING (WAVED)

11 - FRONT CLUTCH RETAINER

6 - REACTION PLATE

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12. Check clutch pack clearance with feeler gauge

(3). Clearance between waved spring and pres-
sure plate should 2.5-4.09 mm (0.098-0.161 in.). If
clearance is incorrect, clutch plates, clutch discs,
snap-ring, or pressure plate may have to be
changed.

SERVO-FRONT

DESCRIPTION

The kickdown servo consists of a two-land piston (3)
with an inner piston (2), a piston rod (7) and guide,
and a return spring (4). The dual-land piston uses seal
rings on its outer diameters and an O-ring for the
inner piston.

OPERATION

The application of the piston is accomplished by applying pressure between the two lands of the piston. The pres-
sure acts against the larger lower land to push the piston downward, allowing the piston rod to extend though its
guide against the apply lever. Release of the servo at the 2-3 upshift is accomplished by a combination of spring
and line pressure, acting on the bottom of the larger land of the piston. The small piston is used to cushion the
application of the band by bleeding oil through a small orifice in the larger piston, diesel engine only. The release
timing of the kickdown servo is very important to obtain a smooth but firm shift. The release has to be very quick,
just as the front clutch application is taking place. Otherwise, engine runaway or a shift hesitation will occur. To
accomplish this, the band retains its holding capacity until the front clutch is applied, giving a small amount of over-
lap between them.

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DISASSEMBLY

1. Remove seal ring (6) from rod guide (5).

2. Remove small snap-ring (7) from servo piston rod

(11). Then remove piston rod (11), spring (10), and
washer (9) from piston (2).

3. Remove and discard servo component O-ring (3)

and seal rings (1, 6).

CLEANING

Clean the servo piston components with solvent and
dry them with compressed air.

1 - PISTON RINGS
2 - SERVO PISTON
3 - O-RING
4 - SNAP-RING
5 - PISTON ROD GUIDE
6 - SEAL RING
7 - SNAP-RING
8 - SERVO SPRING
9 - WASHER
10 - SPRING
11 - PISTON ROD

1 - PISTON RINGS
2 - SERVO PISTON
3 - O-RING
4 - SNAP-RING
5 - PISTON ROD GUIDE
6 - SEAL RING
7 - SNAP-RING
8 - SERVO SPRING
9 - WASHER
10 - SPRING
11 - PISTON ROD

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INSPECTION

Inspect the servo components (1-11). Replace the
springs if collapsed, distorted or broken. Replace the
guide, rod and piston if cracked, bent, or worn. Dis-
card the servo snap-ring if distorted or warped.

Check the servo piston bore for wear. If the bore is
severely scored, or damaged, it will be necessary to
replace the case.

Replace any servo component if doubt exists about
condition. Do not reuse suspect parts.

ASSEMBLY

Clean and inspect front servo components.

1. Lubricate new o-ring (3) and seal rings (1, 6) with

petroleum jelly and install them on piston (2), guide
(5), and rod (11).

2. Install rod in piston. Install spring (8) and washer

(9) on rod. Compress spring (8) and install snap-
ring (7).

CABLE-GEARSHIFT

DIAGNOSIS AND TESTING - GEARSHIFT CABLE

1. Engine starts must be possible with shift lever in PARK or NEUTRAL positions only. Engine starts must not be

possible in any other gear position.

2. With the shift lever in the:

a. PARK position - Apply upward force on the shift arm and remove pressure. Engine starts must be possible.

b. PARK position - Apply downward force on the shift arm and remove pressure. Engine starts must be pos-

sible.

c. NEUTRAL position - Normal position. Engine starts must be possible.

d. NEUTRAL position - Engine running and brakes applied, apply upward force on the shift arm. Transmission

shall not be able to shift from neutral to reverse.

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